Development and psychometric evaluation of the Environment-Behavior Interaction Code (EBIC)

Background: Although the behavioral changes with progressive dementia are s een to increasingly depend on the environmental context until late stage di sease, measurement has not reflected this interaction in real time to allow examination of antecedents to disruptive behavior. Objectives:To develop and evaluate the psychometric properties of the Envir onment-Behavior Interaction Code (EBIC) for use in dementia care research w ith either sequential or non sequential analyses of behavioral data. Method: Development of the cmputer-based (sequential event format) EBIC pro vided an observational coding system to classify all behavior and environme ntal context in real time, so that the probability of social enviromental a ntecedents to resident disruptive behavior could be estimated mated. A chec klist (interval format) EBIC, based on the same behavioral taxonomy, was de veloped for clinical outcome research. A total of 158 elderly residents of dementia care units were purposively selected from three large long-term ca re facilities for the psychometric study components. Results: Psychometric results indicated significant (p < 0.01) known-groups validity for the disruptive behavior construct, which was defined as a com posite of aversive, harmful, and high intensity neutral behavior. Interrate r agreement for the event format of the EBIC was estimated by average kappa (0.65) and percentage agreement (78%). For the interval format, the mean i nterrater kappa was 0.80 with 96% agreement. Stability of the event format using a 2-week retest interval ranged from r = .50 (positive behavior) to r = 0.73 (negative behavior, defined as aversive + harmful). On replication with a new sample, stability was higher for positive (r = 0.92) and negativ e (r = 0.95) components, and for composite scores of nondisruptive (positiv e + low intensity neutral r = 0.65) and disruptive (r = 0.85) behavior. Conclusion: This research provided support for the reliability and validity of both event and interval EBIC formats. Measurement using the EBIC taxono my has applicability to dementia care research questions that call for eith er sequential analysis of social interactions or nonsequential analysis of behavioral outcomes in intervention studies.